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A complete turbine control system includes the following functional systems: (1) Monitoring system. The monitoring system is an essential device to ensure the safe operation of the turbine, as it can continuously monitor changes in various parameters of the turbine. Turbine parameter monitoring is typically carried out by a DAS system; the measurement results are sent to the control system as constraints, to the protection system as protection conditions, and to the sequence control system as control parameters. (2) Protection system. The function of the protection system is to enable the protective devices to act promptly based on the actual situation in case of a fault in the power grid or the turbine itself, thereby stopping the turbine from operating or taking certain measures to prevent the accident from worsening or causing damage to the equipment. The protection functions of large-capacity steam turbines include overspeed protection, low oil pressure protection, axial displacement protection, expansion difference protection, low vacuum protection, vibration protection, etc. (3) Control system. The closed-loop control system of a steam turbine includes a speed control system, a power control system, a pressure control system, etc. (4) Online thermal stress monitoring system. Thermal stress cannot be measured directly; it is usually calculated indirectly using modeling methods by measuring the temperature values at certain specific points in the turbine. In addition to being used for monitoring, the results of thermal stress calculations can also be used to correct the turbine acceleration rate and load change rate. (5) Steam turbine automatic start-stop control system. The turbine automatic start-stop control system is capable of carrying out the entire process, including turning the turbine, evacuating the vacuum, accelerating it for grid connection, operating under load, operating at full load, as well as reducing the load and shutting down the turbine. The prerequisite for enabling the automatic start and stop of the turbine is that all necessary control systems are available and can operate properly. These systems include automatic control systems, monitoring systems, thermal stress calculation systems, and bypass control systems, among others. (6) Hydraulic servo system. The hydraulic servo system consists of a turbine oil supply system and a hydraulic actuator. The oil supply system provides pressurized oil to the hydraulic actuator. The hydraulic actuator consists of components such as electro-hydraulic converters, hydraulic motors, and position sensors, and its function is to control the operation of the corresponding valves according to the instructions from the electronic control system.